International Journal of Innovative Science and Modern Engineering (IJISME) ISSN: 2319-6386, Volume-2, Issue-6, May 2014

6 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Pvt. Ltd.

Abstract— Micro strip antennas are finding a growing

medical application in imaging, diagnosis, and treatment. In this paper an optimized E-shaped patch antenna is presented. This paper presents a flexible micro strip antenna that can be placed in contact with the human skin. Microwave breast imaging (MBI) uses low power and longer wavelength signals to obtain information about breast tissues, and promises a safer and more accurate modality for regular breast scanning. In this paper, a method is shown to reduce the effect of signal reflection from the breast skin by placing the antenna in-contact with the breast skin. The skin can be considered a layer of the antenna substrate. This reduces the signal scattering from the skin and more transmitted signal is irradiated on the tumor, thus, increasing the tumour detection sensitivity. Design and simulation in Ansoft High Frequency Simulation Software (HFSS) is presented.

Index Terms—wireless communications, patch antenna, tumour, imaging Cancer, Patch Antenna, High Frequency Simulation Software.

I. INTRODUCTION In 2009, more than 192 thousand new cases of breast cancer were expected in the United States and more than 40 thousand women were estimated to lose their lives. Antennas have long been used in many medical applications including, microwave imaging, medical implants, hyperthermia treatments, and wireless wellness monitoring. Reducing the size and complexity of the antennas used in these applications has been the primary objective of recent antenna research. In 2007, 1.3 million new cases of breast cancer and 465 thousand deaths were estimated worldwide. Microwave imaging of biological compositions have developed an enormous amount of attention because of its ability to access the breast for imaging.MBI infrastructure consists of several deficiencies that conclude ex-vivo circumstances, electromagnetic (EM) signals coupled with giga-hertz signal frequencies. An understanding of the breast tissue and skin diplomacy is documented to help one better understand how current methods detect as well as acknowledge between healthy and malignant tissue. The design and simulation of microwave breast imaging using 2.54 GHz signal has been presented. HFSS has been used for the modeling and simulation. While, the experimental implementation of the concept is still in progress, the simulation results presented shows that the direct placement of the antenna on the breast skin can significantly increases the sensitivity of the MBI systems.

Manuscript received on May, 2014.

Maneesha Nalam, Electronics and Communication, Amity University/ Amity School Of Engineering, Noida, Uttar Pradesh, India.

Nishu Rani, Electronics and Communication, Amity University/ Amity School Of Engineering, Noida, Uttar Pradesh, India.

Prof. Anand Mohan, Master Of Computer Science, NSHM Business School, Shibtala, Durgapur, West Bengal, India.

The microwave breast imaging technique utilizes the signal scattering by an object when the object is illuminated by an electromagnetic signal. The signal scattering by an object depends on various factors, including the environment, signal strength, and the material properties of the object. For a given signal source and the environment, the scattered signal depends on the electrical properties of the object, especially dielectric and conductivity. This principal is utilized to detect the tumour in the breast using microwave signals. The breast tumours have very distinct electrical properties (higher dielectric permittivity and higher conductivity), which allows them to detect by analysing the scattered signals. As shown in Figure 1, the amount of signal scattered by a breast tumour is higher than that of normal breast tissues, which can be received by a separate antenna or the property change of the transmitting antenna due to the scattered signals, can be analysed and utilized for the tumour detection.

II. WIRELESS PANS (PERSONAL ANTENNA NETWORK) IN MEDICAL APPLICATIONS

The aim is the creation of a patient-cantered RF hub that can receive vital signs from patients, concentrate them and send them to a base station in a relatively short range via a wireless personal area network. WPANs can be used for connecting to a higher level network and the Internet (uplink) and even for wireless communication among the ECG sensors themselves (intrapersonal communication). The criteria that are mostly considered for the selection of the most appropriate and efficient protocol in this area are: Data rate Range Low battery power requirement Safety and reliability Security Data Latency One very widely spreading application in Biomedical Science is Non-Invasive Method Investigation for Blood Pressure Measurements. The old traditional way of checking Blood Pressure is called Cuff method and this new method is done with Arterial tonometer which is a biomedical application of Antenna. Cuff Accurate Non-continuous monitoring Discomfort from pressure Arterial Tonometer Applies constant pressure on artery at the wrist Constant pressure creates discomfort

Biomedical Application of Microstrip Patch Antenna Maneesha Nalam, Nishu Rani, Anand Mohan

Biomedical Application of Microstrip Patch Antenna

7

Published By: Blue Eyes Intelligence Engineering & Sciences Publication Pvt. Ltd.

Fig.1 Earlier Method used to check Blood Pressure

Fig.2 Arterial Tonometer investigation for Blood pressure

III. PHYSICAL PARAMETERS OF THE ANTENNA The antenna parameters of this antenna can be calculated by the transmission line method, as exemplified below. Width of the Patch The width of the antenna can be determined by

Length of the Patch The effective constant can be obtained by :

Where = Effective dielectric constant

= Dielectric constant of substrate h = Height of dielectric substrate W = Width of the patch The dimensions of the patch along its length have now been extended on each end by a distance ΔL, which is given empirically by

The actual length L of the patch is given as

Feed Location Design The position of the coaxial cable can be obtained by using:

Where = propagation constant

IV. DESIGN METHODOLOGY

Parameters Used Value Frequency 1.89 & 2.4GHz Input impedance 50Ω Di electric coefficient 39 Conductivity 1.1S/m Height (substrate) 16mm Patch length 40mm Patch width 10mm

Table 1

Fig. 3 Schematic diagram of Antenna Skin Substrate

V. DESIGN OF ANTENNA IN HFSS

Fig. 4: Antenna in HFSS Design

Fig. 5: Antenna in HFSS Design with probe feed

International Journal of Innovative Science and Modern Engineering (IJISME) ISSN: 2319-6386, Volume-2, Issue-6, May 2014

8 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Pvt. Ltd.

VI. RESULTS Using the substrate parameters, an initial rectangular patch antenna was designed and simulated without any skin layer. The simulated |S11| parameter in dB (20 log10 |S11|), will be called as |S11| hereafter) and the radiation pattern of a flexible micro strip antenna. After tuning the antenna for 1.9 and 2.45 GHz, the antenna was fabricated. The optimised antenna model was used to simulate with the breast models developed in HFSS.

Fig. 6: Experimental |S11| of the Antenna

Fig. 7: VSWR of the Antenna

Fig. 8: Radiation pattern of the Antenna

VII. CONCLUSION A flexible micro strip antenna developed for skin contact application has been presented. The presented planer flexible antenna can be used in wide varieties of medical applications, including, in developing wearable medical

devices. In this paper, the prospect of an antenna that can be placed on the breast skin has been presented and a simple antenna design for the case has been discussed.

REFERENCES [1] Smith, R. A., D. Saslow, K. A. Sawyer, W. Burke, M. E. Costanza, W.

P. Evans, R. S. Foster, E. Hendrick, H. J. Eyre, and S. Sener, \American cancer society guidelines for breast cancer screening: Updated 2003," CA: A Cancer J for Clinician, 141169, 2003.

[2] Epstein, S. S., R. Bertell, and B. Seaman, \Dangers and unreliability of mammography: Breast examination is a safe, effective, and practical alternative," International Journal of Health Services, 605615, 2001.

[3] Nass, S. J., I. C. Henderson, and J. C. Lashof, \Mammography and beyond: Developing technologies for the early detection of breast cancer," National Cancer Policy Board, Institute of Medicine, National Research Council, 2001.

[4] Y. Rahmat-Samii and E. Michielssen, Electromagnetic Optimisations by Genetic Algorithms, New York, NY: Wiley, 1999.

[5] R. Matouek, Realization of Fuzzy-Adaptive Genetic Algorithms in a Matlab Environment, Institute of Automation and Computer Science, Brno University of Technology, 2001.

[6] D. M. Pozar, "Microstrip antenna coupled to a microstrip-line, Electron.Lett” vol. 21, no. 2, pp. 49-50, Jan. 1985.

[7] P. Katehi, N. Alexopoulos, and I. Hsia, "A bandwidth enhancement method for microstrip antennas,, vol.35 no.1, pp.5-12, Jan 1987.

Maneesha Nalam completed her M.Tech degree from Amity University Noida Uttar Pradesh in Electronics and communication and her paper has been published in image processing domain. Her future works are on wireless sensors.

Nishu Rani completed her M.Tech degree from Amity University Noida Uttar Pradesh in Electronics and communication and her paper has been published in image processing domain. Her future works are on Geological and geomorphological image and its enhancement.

Prof. Anand Mohan has completed his Masters degree in Computer science and presently working as an assistant professor at NHSM Business School Durgapur West Bengal. He has lot of work published in domains like computer science; Image processing, antenna and networking.